We have now demonstrated a specific binding site for tocopherol in the purified, isolated adrenal cell membrane. We further have established the kinetics of the binding. During this grant period, we propose to further identify the nature of this binding material as to its chemical identity being protein, glycoprotein or lipoprotein by utilizing biochemical probes such as phospholipase A, phospholipase C, sulfhydryl inhibiting agents or protease inhibitors such as trypsin or pronase. The secend phase of this research will deal with the role of prostaglandin in steroidogenesis. As we have demonstrated lack of effect of major prostaglandins in steroidogenesis, we will continue to work in collaboration with other investigators who have worked with us in measuring prostaglandin E1 and E2. Although our preliminary studies on prostaglandin E1 suggest the absence of such a prostaglandin in response to ACTH, we do not know the effect of ACTH on prostaglandin E2 series. Furthermore, prostaglandin inhibitors such as indomethacin will be used to measure steroidogenesis as well as formation of immunoreactive prostaglandin E1. Finally, we will continue to evaluate the effect of numerous steroidogenic substances and inhibitors on adenyl cyclase of adrenal cell membrane. Although our studies on liver cell membrane suggest lack of difference between vitamin E sufficient (plus E) and deficient (minus E) rats, these studies have not been fully elucidated in adrenal tissue. Therefore, plans are to investigate NaF, glucagon, and ACTH-induced adenyl cyclase activities in the plus E and minus E adrenal cell membrane in the presence and absence of ascorbate and GPP (NH)P. Attempts will be made to purify adenyl cyclase activity from these membranes to see if this material could be separated from the specific tocopherol binding substance.